You can position a datum point by selecting two edges on the model and entering the distance from the datum point to each edge.
To create a datum point by specifying the distance from two edges:
From the main menu bar, select Tools
Datum.
The Create Datum dialog box appears. The dialog box outlines the types of datum geometry you can create.
ABAQUS/CAE displays prompts in the prompt area to guide you through the procedure.
Tip:
You can also create a datum point using the 
tool, located in the module toolbox. For a diagram of the datum tools in the toolbox, see “Using the Datum toolset,” Section 40.2.
From the list of types at the top of the dialog box, choose Point.
The Method list indicates the methods you can use to create a datum point.
From the Method list, select Offset from 2 edges and click OK.
From the part or assembly in the current viewport, select the plane on which to create the datum point.
Select a straight edge on the specified plane and enter the distance of the datum point from this edge.
Select a second straight edge on the plane and enter the distance of the datum point from this edge.
The datum point appears. You can modify the position of the datum point by selecting FeatureEdit from the main menu bar and modifying the distance from the datum to each edge.
